This application claims the priority of Korean Patent Application No. 2003-78333, filed on Nov. 6, 2003, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.
1. Field of the Invention
The present invention relates to a current-jump-control circuit including an abrupt metal-insulator phase transition device.
2. Description of the Related Art
In recent years, instead of a metal oxide semiconductor field effect transistor (MOSFET) having a limitation in decreasing the channel length, a Mott field effect transistor (FET) has been proposed, which uses a Mott insulator as the channel layer. Since the Mott FET utilizes a metal-insulator phase transition that is successively generated, it is necessary to add electrons or holes to be used as a charge carrier until a metallic characteristic appears most well, which causes a limitation that the added charge should be in a high concentration state. Accordingly, a method using an insulator that shows an abrupt metal-insulator phase transition characteristic of a current jump under a constant condition has been recently proposed instead of an insulator showing a continuous metal-insulator phase transition, and is disclosed in U.S. Pat. No. 6,624,463. A field effect transistor disclosed in U.S. Pat. No. 6,624,463 shows an abrupt metal-insulator phase transition characteristic of a current jump induced by doping of a small hole concentration.
FIG. 1 is a graph showing electric field-current density characteristic of a current jump of a device manufactured using a material showing such an abrupt metal-insulator phase transition.
Referring to FIG. 1, when an electric field (Efield) of a predetermined level, for instance, of 7 MV/m is applied to both terminals of the device, the abrupt metal-insulator phase transition device is abruptly phase-transited from an insulator to a metal, so that a large amount of current flows through both terminals of the device. Thus, when a large current above a limitation current flows, the device may not endure against the large current and may be failed. Through the present specification, a device, which causes an abrupt metal-insulator phase transition when an electric field above a critical value is applied, is defined as “abrupt metal-insulator phase transition device.”
As aforementioned, in the abrupt metal-insulator phase transition device, an abrupt metal-insulator phase transition may generate a large amount of current (current jump) abruptly. To this end, the abrupt metal-insulator phase transition device needs a control circuit that can control the current jump so as to endure this large amount of current.